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Posted By: sparkync 120/208 volt/240 volts - 04/12/17 01:08 AM
I'm posting another question on another subject. Didn't want to confuse the two together. I have another job where a piece of equipment needs 240 volts. The nameplate on the panel says 120/208. That's pretty self explanatory, but then under it, it has 240 volts. Why would it have both voltages on the same panel nameplate? I'm under the assumption that I would have to set a "buck boost" transformer to get the 240 I need. Am I missing something?

Thanks
Posted By: andey Re: 120/208 volt/240 volts - 04/13/17 12:00 PM
What kind of equipment is it? Electronic / solid state power supply? one, two, three phase?
There are modern electronic equipments that self-adapt to the line voltage, as most Computer power supplies nowadays read something like "100...240V".
Can the manufacturer still be contacted? That would be the best way to be sure
Posted By: sparkync Re: 120/208 volt/240 volts - 04/13/17 06:25 PM
Equipment is a deep fat fryer, that emphatically states not to hook it up on any voltage other than what is required, which is 240 volts.
Posted By: gfretwell Re: 120/208 volt/240 volts - 04/13/17 07:20 PM
I imagine it might not be able to reach it's full capacity at 208v. It will still work but if you are cooking lots of stuff in quick succession it may not be able to keep up. This may end up being a pretty big transformer too.
This also may explain why that cluster of restaurants I mentioned in Key West still clings to it's delta supply. It is the only one I have ever seen that had 3 transformers. I bet they were all heavily invested in 240v cooking equipment.

[Linked Image from gfretwell.com]
Posted By: SteveFehr Re: 120/208 volt/240 volts - 04/15/17 09:47 PM
Don't confuse the panel enclosure with the panel bus assembly. Panel enclosures are often listed for use at different voltages, and will have a generic one-label-fits-all covering all the applications that enclosure is used for. It doesn't mean that it IS either of those voltages, just that it's listed for it and could come with either voltage. You'll need to check and see if that panel is wired 120/208Y or 120/240V 1-phase.
Posted By: bigpapa Re: 120/208 volt/240 volts - 04/16/17 06:51 AM
Anything with a heating load component is gonna use significantly less wattage. Induction motors won't like it either.
Posted By: sparkync Re: 120/208 volt/240 volts - 04/17/17 12:47 PM
Already verified at the equipment that it has 211 volts, which is obviously a 120/208 service. The customer is getting someone else to hook the fryer up. The only way he can hook it up right and according to the nameplate of the new fryer, is to set a buck boost transformer which I have already ordered and the customer don't want to pay for. The other electrician told her hooking it up on 208 volts should work ok, but I told her she would be voiding the warranty. My original post was wondering if I had missed something. When I told her if he didn't hook it up right, it would void the warranty, she said he was going to hook it up right frown
How can that be without a transformer? Either he's a fly by night electrician or I'm missing something terribly bad. The manual specifically says NOT TO HOOK IT UP OTHER THAN WHAT'S ON THE NAMEPLATE.:(
Thanks again.
Posted By: gfretwell Re: 120/208 volt/240 volts - 04/17/17 07:18 PM
I think I would try to talk to the manufacturer. These things are usually just toaster wire in a submerged element and the effect of a lower voltage is just lower heat output. Performance would be the main problem. It might not recover from successive loads of frozen fries as fast as it is supposed to. Of course in a high volume operation that might be a show stopper. Have they looked to see if there is a 208v element?
That would probably be cheaper than a transformer.
Posted By: SteveFehr Re: 120/208 volt/240 volts - 04/17/17 11:27 PM
I agree with Greg, ask the manufacturer. If it's just resistance heat, hooking it up 211V would give 77% of the rated power which means it would take a little longer to warm up and might not be worth the cost of a boost transformer.
Posted By: sparkync Re: 120/208 volt/240 volts - 04/18/17 01:05 AM
We got the one that sent them the equipment on the phone right after we found that "she" ( my customer) had ordered the wrong one. They told her just what I had told her, but we called just to verify it. She had it on speaker phone so there were several witnesses. Even after that she still decides to get someone else to hook it up on 208 volts. I guess it her problem, except she was the one who told me to go ahead and order the transformers, then 2 days later tells me to cancel the order. Only problem is that they were already shipped frown Now she will have to pay a 20% restocking fee plus freight both ways for them to take them back. Anyway, thanks for the input. When she said the other electrician was going to hook it up right, I just wanted to make sure I wasn't missing something. Maybe he's already got the transformers, I don't know. Thing about it, it sure will void the warranty if something ever happens to it.

Thanks again..
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